If you get an occasional bird dropping in the water, it's not going to cause the kind of CC's that you are experiencing--I have swallows that drink out of my pool and regurg stuff on a regular basis, and my CC never goes above 0.5.

Other than keeping the pool at shock level to burn off the CC, I don't really know what to tell you to do other than try to identify where they're coming from. Is it possible that the pool surface is degrading and causing it? Are you positive that your testing methods are correct and that you're using fresh reagents? I know those questions are redundant, but I'm just muddling over your situation trying to figure out what other approach we can take. I understand your frustration and would feel the same way--but don't give up on it yet...

Janet